Rear main seal leak and need advice

[Beekeeper]

I know this subject has been beat to death and yes I have read all the recent threads on here and moparts and dodgecharger about the different ways to fix this and the opinions on what works. I would like to do this one time and be done with it so the question is should I go with a rope seal with factory retainer or try the rubber seal using the directions Hughes engines has? The crank is an older eagle with the grooves to direct the oil back in the engine. The current set up is a rubber seal with a billet retainer not sure who made the retainer. Also have seen the one piece seal from fast fish but don’t have any experience with it.
Engine is a 426 hemi

 

[Potts]

My experience is with a 383.
I tried the Vitton rubber seal from Mancini Racing twice.
Once with the Vitton rubber only.
Once with the Billett cap too.
Still leaks while cruising.

 

[65hemi]

The rear main seal on my hemi leaked from start up on the dyno. The builder made an attempt to repair the leak. It leaked again on start up in the car. When I freshened the motor I used the fast fish one piece seal. Didn’t notice any leak on the dyno, but in the car the damn thing still leaks.

 

[Beekeeper]

Yea it’s terrible we can’t get good products for the rubber seal any longer. I’m really leaning toward pulling the crank and using a rope seal.

 

[69Bee]

I use the OEM retainer on ALL Mopar engines, a rubber seal that comes in the Fel-Pro gasket set, and the seal gets installed even with the parting lines on the mains (not offset). I will hex myself, and say that I have never had a rear main seal lead on me. One thing to remember is that the side seals for the seal retainer are not like the old Mopar kind that swell up. Fel-Pro finally got rid of the stupid pipe cleaners, and are now including rubber side seals. They can be difficult to install, but take your time. I use moly assembly lube on the side seals (both sides), on the block uprights sides, and in the retainer grooves. I put the side seals on the retainer with maybe a 1/4" below the bottom and let the seals start in the block. Don't worry if they want to look like a "V", the important part is that they start before the retainer does. Once the retainer starts, tap on the retainer and side seals carefully to get them all to go down. Once the retainer and seals are home, wipe all of the lube off. The last thing I do is to apply some Ultra-Grey" RTV in the vertical space between the retainer and the block (the sides). Also, when I put the rear main seals in the block and retainer, I put a small bead of the "Ultra-Grey" across the back rib of the seal so that it will seal between the block/seal and retainer/seal. I am sure you know this, read about this, or whatever, but this my procedure for the rear mains on all engines (2pc seals) that I do. I have installed one of the "Gee-Whiz" one piece seals that you cut and rotate on for a Pontiac, and what a POS in my personal opinion.

 

[69Bee]

Yea it’s terrible we can’t get good products for the rubber seal any longer. I’m really leaning toward pulling the crank and using a rope seal.

Rope seals leak as a function of their operation. They are also a "PITA" to install. Not saying I can't, but they just suck to put in. The last one I put in was a rope kit for a '49 buick from Best Gasket, and I feel that they have a different rope that they use because it cut really easily, where they usually are a pain to cut. In the past, I used a X-Acto to get a slit started, then removed the seal and finished the cuts with tin snips!

 

[69L48Z27]

^^^^ Same here with Felpro and stock retainer.

 

[Beekeeper]

I have already decided that the billet retainer is not going back in. On the retainer I’m gonna use ultra gray without the side seals just gotta make a decision on rope or rubber for the seal. So what’s the part number on the felpro you guys are using?

 

[padam]

I used Challenger340's method with a normal felpro rubber seal and no side seals, and no leaks.
But my seal groove did seem to be concentric.

Edit:
Well, none from the rear main. Dipstick tube and oil pan were other matters, but are fixed now.

 

[65-440]

Stock retainer with a felpro high vacuum rear main seal, no leaks... seal offset with ultra black rtv on the parting lines.

 

[Fran Blacker]

Have you thought about a "anti" leak number 5 main bearings? don't know if they help or if they're available. I might have an std NOS one.

 

[Beekeeper]

Have you thought about a "anti" leak number 5 main bearings? don't know if they help or if they're available. I might have an std NOS one.

I sure have and even thought of grooving the bearing I have may not do diddley squat but it’s a good thought anyway.. They are std. bearings

 

[Runcharger]

Anytime I've had a rear main seal leak a Felpro and good sealer on the retainer sides fixed it. I think the retainer sides are generally the root cause.

 

[BSB67]

Stock retainer. Rubber seal. Never a leak.

 

[1967coronet]

Just a thought.
Could crank case pressure be causing many of the rear main leaks ?
I see quite a few engines running no pcv valve .
Just a breather set up.
Some years back I tried running a 383 with a breather only in each valve cover . Never could get that engine sealed up until I switched to pcv valve on one side and breather on the other.

 

[Beekeeper]

Just a thought.
Could crank case pressure be causing many of the rear main leaks ?
I see quite a few engines running no pcv valve .
Just a breather set up.
Some years back I tried running a 383 with a breather only in each valve cover . Never could get that engine sealed up until I switched to pcv valve on one side and breather on the other.

I do think that is a contributor to some of the seal leaks

 

[erickson]

I use the Mancini billet kit and cut .030 off the Mating surface I’ve had good luck doing this

 

[1967coronet]

I do think that is a contributor to some of the seal leaks

I always thought so to beekeeper after my mistake.
Like some of the other guys posted, I used the felpro split rubber/vinton? Seal with blue plastic side strips. Little dab of ultra grey at the parting joints and had good luck with this last 440.
I know fixing a leak gets damn frustrating.

 

[blue69runner]

RVT on the seal retainer.

 

[Potts]

The question remains.
If the leak stops and just the residual drips when you are parked, is that a crankcase pressure issue only?
OR
If the Oil continues to drip alot when parked over time, would that be a better example of a rear main seal issue?